The Effect of Crystallinity and Microstructure on Corrosion Resistance of Atmospheric Plasma Sprayed Cu-based Bulk Metallic Glass Coating

In this study, Cu-based bulk metallic glass (BMG) coatings were built-up through atmospheric plasma spraying (APS) process with the different process parameters, i.e., hydrogen flow rate. As the hydrogen flow increases, thermal energy in plasma flame increases and this induces the differences in the melting state of Cu-BMG particles and deposition characteristics, e.g., deposition efficiency, porosity, and adhesion state of particles. Crystallization and oxidation of Cu-based BMG and its distribution were analyzed through differential scanning calorimeter and scanning electron microscopy. As thermal energy in the plasma flame increases, the melting fraction and oxidation of particle in the coating increases. The corrosion resistance of Cu-based BMG coatings sprayed at the different process conditions was evaluated. And the analysis on corrosion resistance is discussed mainly based on the crystallinity, oxidation, and microstructural characteristics of Cu-based BMG coatings.